Elastic fabric including elastic fiber and hard yarn and methods for making

ABSTRACT

Methods for making stretch fabric having stretch between 10% to 45% in the weft and/or warp direction are disclosed. A corespun composite elastomeric yarn is produced either (a) by low draft (2.7× or below) core-spinning of the elastomeric yarn, or (b) by pretreating the corespun composite yarn in steam or heated water at temperatures of at least 110° C. to reduce yarn power before dyeing or weaving. The fabric with such corespun composite elastomeric yarn in the weft meets end-use specifications without heat-setting.

This application is a continuation-in-part of U.S. application Ser. No.11/268,112, filed on Nov. 7, 2005, which claims the benefit of U.S.Application No. 60/626,698 filed Nov. 10, 2004, both of which areincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to methods for making corespun composite elasticyarns and stretch woven fabrics from such yarns.

2. Summary of the Related Art

Stretch woven fabrics have been produced for nearly 30 years. Thoseworking in the textile industry, such as yarn spinners, weavers,dyers/finishers, cutters and designers, understand that consumers desirefabrics and garments made with quality standards. However, lightweightstretch woven shirting fabrics (weighing less than 175 g/m²) generallyare more difficult to produce since normal elastane fibers such asspandex have too much stretch power, and thus too tightly contract,resulting in fabrics that are too tight and too heavy. The jammed fabricstructure results in shirting fabrics with higher shrinkage, a harsher,non-cottony fabric hand, and thermal discomfort during wear.Heat-setting may be a necessary step in the process to makinglightweight (less than 175 g/m²) spandex stretch shirting fabrics withhigh comfort.

Even for heavy weight jeans, it is still difficult to produce denim withstretch in warp direction. There are some limited warp stretch denims inthe market; however, these fabrics have undesirable properties includinghigh shrinkage, high shrinkage variation, significant weft yarndistortion and excessive stretch.

The warp yarns in denim are usually dyed into blue or black color withan indigo dye before weaving. The unique hue of clothes made from wovenfabric dyed with indigo dye and the favorable change in that hue whichoccurs over time and after repeated washing by bleaching make itpossible to design articles of clothing based on this sensitivity to huechange.

Most stretch woven fabrics are made with elastomeric yarns in thedirection in which the stretch will exist. For example, elastomericyarns are used as warp yarn in order to make warp stretch fabrics.

Typically, stretch denim can use composite yarn made with 70 denier (78dtex) and 40 denier (44 dtex) spandex. The spandex (elastane) can bestretched to about 3.5× to about 4.0× machine draft during the yarncovering process. Such typical core spun yarn can have a high stretch.During the indigo yarn dyeing process under hot water, a stretchedelastane fiber will recover causing the core spun combination yarn toshrink and subsequently coil and twist together. This shrinking andtwisting makes it difficult to keep the yarn straight in furtherprocessing. After yarn dyeing, a non-uniform yarn sheet having anon-uniform tension amount the yarns is difficult to use in a warpingand weaving operation. These difficulties may reduce the beaming andweaving efficiency or even make operation impossible, due to yarn endbreaking, machine stopping and unacceptable fabric appearance.

Moreover, the fabrics made from such yarns have poor quality.Specifically, these fabrics have high wash shrinkage, dimensionalinstability, poor recovery and high skew on the fabrics.

For stretch woven fabric, most of the elastomeric yarns are used incombination with relatively inelastic fibers, such as polyester, cotton,nylon, rayon or wool. These relatively inelastic fibers sometimes arecalled “hard” fibers.

Elastomeric fibers are commonly used to provide stretch and elasticrecovery in woven fabrics and garments “Elastomeric fibers” are either acontinuous filament (optionally a coalesced multifilament) or aplurality of filaments, free of diluents, which have a break elongationin excess of 100%, independent of any crimp. An elastomeric fiber when(1) stretched to twice its length, (2) held for one minute; and (3)released, retracts to less than 1.5 times its original length within oneminute of being released. As used in this application, “elastomericfibers” should be interpreted to mean at least one elastomeric fiber orfilament Such elastomeric fibers include, but are not limited to, rubberfilament, biconstituent filament and elastoester, lastol, and spandex

“Spandex” is a manufactured filament in which the filament-formingsubstance is a long chain synthetic polymer comprised of at least 85% byweight of segmented polyurethane.

“Elastoester” is a manufactured filament in which the fiber formingsubstance is a long chain synthetic polymer composed of at least 50% byweight of aliphatic polyether and at least 35% by weight of polyester.

“Biconstituent filament” is a continuous filament comprising at leasttwo polymers adhered to each other along the length of the filament,each polymer being in a different generic class, for example, anelastomeric polyetheramide core and a polyamide sheath with lobes orwings.

“Lastol” is a fiber of cross-linked synthetic polymer, with low butsignificant crystallinity, composed of at least 95% by weight ofethylene and at least one other olefin unit. This fiber is elastic andsubstantially heat resistant.

A “covered” elastomeric fiber is one surrounded by, twisted with, orintermingled with hard yarn. The covered yarn that comprises elastomericfibers and hard yarns is also termed a “composite yarn” in thisapplication. The hard-yarn covering serves to protect the elastomericfibers from abrasion during weaving processes. Such abrasion can resultin breaks in the elastomeric fiber with consequential processinterruptions and undesired fabric non-uniformities. Further, thecovering helps to stabilize the elastomeric fiber elastic behavior, sothat the composite yarn elongation can be more uniformly controlledduring weaving processes than would be possible with bare elastomericfibers.

There are multiple types of composite yarns, including: (a) singlewrapping of the elastomer fibers with a hard yarn; (b) double wrappingof the elastomer fibers with a hard yarn; (c) continuously covering(i.e., core spinning) an elastomer fiber with staple fibers, followed bytwisting during winding; (d) intermingling and entangling elastomer andhard yarns with an air jet, and (e) twisting an elastomer fibers andhard yarns together. The most widely used composite yarn is acotton/spandex corespun yarn. A “corespun yarn” consists of a separablecore surrounded by a spun fiber sheath. Elastomeric corespun yarns areproduced by introducing a spandex filament to the front drafting rollerof a spinning frame where it is covered by staple fibers.

A representative core-spinning apparatus 40 is shown in FIG. 1. Duringcore-spin processing, an elastomeric fiber, such as spandex, is combinedwith a hard fiber to form a composite corespun yarn. The spandex fromtube 48 is unwound in the direction of arrow 50 by the action ofpositively-driven rollers 46. The rollers 46 serve as a cradle for thetube 48 and deliver the spandex filament or yarn 52 at a pre-determinedspeed.

The hard fiber or yarn 44 is unwound from tube 54 to meet the spandexfilament 52 at the set of front rollers 42. The combined spandexfilament 52 and hard fiber 44 are core-spun together at spinning device56.

The spandex filament 52 is stretched (drafted) before it enters thefront rollers 42. The spandex is stretched through the speed differencebetween feed rollers 46 and front rollers 42. The delivery speed of thefront rollers 42 is greater than the speed of the feed rollers 46.Adjusting the speed of the feed rollers 42 gives the desired draft,which is known as the machine draft. Normally, the machine draft forcorespun elastomeric composite yarns is from about 3.0× to about 4.0×including from about 3.0× to about 3.8×. This corresponds to a spandexelongation of 200% to 300%, or more. The stretching of the spandeximparts elasticity to the final corespun yarn because the spandex corewill retract when stress is removed, thus compacting and bulking thespun yarn cover. The resulting composite yarn can then be extended tothe point where the non-elastic cover yarn is stretched to its limit

Referring to FIG. 2, a representative method for making a core-spunelastomeric yarn and weaving that yarn to form a stretch fabric isdisclosed. The elastomeric fiber and hard yarn, denoted as cotton inFIG. 2, are combined by core-spinning such as by the apparatus of FIG.1, to form a composite corespun yarn 10. In the example processingmethod set out in FIG. 2, this composite corespun yarn is twist set 12(i.e., treated with steam at temperatures of about 70° C. to about 80°C., sometimes up to 110° C.), wound 14, scoured, and/or bleached anddyed 16, rewound 18, woven into a shirting fabric 20, singed 21,de-sized 22, scoured, and/or bleached and dyed 24 and heat set attemperatures of 190° C. or greater 26, and sanforized 28.

For shirting, the yarn preparation processes may include scouring and/orbleaching, and dyeing including package dyeing. For denim, the yarnpreparation processes may include yarn rope dyeing, slasher dyeing, andbeam dyeing.

Heat-setting 26 “sets” spandex in an elongated form This is also knownas re-deniering, wherein a spandex of higher denier is drafted, orstretched, to a lower denier, and then heated to a sufficiently hightemperature, for a sufficient time, to stabilize the spandex at thelower denier. Heat-setting therefore means that the spandex permanentlychanges at a molecular level so that recovery tension in the stretchedspandex is mostly relieved and the spandex becomes stable at a new andlower denier. Heat-setting temperatures for spandex are generally in therange of 175° C. to 200° C. Heat-setting conditions for conventionalspandex are about 45 seconds or more at about 190° C.

Typically, stretch woven fabrics are made with composite yarns thatincorporate spandex having from about 30 denier (33 dtex) to about 70denier (78 dtex) including from about 30 denier (33 dtex) to about 40denier (44 dtex). The spandex can be stretched to about 3.0× to about4.0× machine draft during the yarn covering or core-spinning process(step 10 in FIG. 2). The composite yarn is woven to form a fabric. Ifthe resulting fabric is not heatset (step 26 in FIG. 2), these wovenfabrics can have high stretch, high fabric recovery, and a syntheticfabric hand. Typically, stretch woven fabrics, which are made withcomposite yarns of from 30 to 70 denier spandex drafted to about 3.5× to4.0× machine draft, contract too much after the fabric finishingprocesses, creating a heavy fabric with a poor hand.

To improve the fabric hand and reduce the fabric recovery power ofstretch woven fabrics, the heat-setting step (step 26 in FIG. 2) usuallyis required during fabric finishing For heat-setting, the fabric isapplied to a tenter frame and heated in an oven. The tenter frame holdsthe fabric on the edges by pins, and stretches it in both the length andwidth directions while in the oven in order to heat set the elastomericfiber or yarn and return the fabric to desired dimensions and basisweight.

In conventional fabrics, if heat-setting 26 is not used to “set” thespandex, the fabric may have high shrinkage, excessive fabric weight,and excessive elongation, which may result in a negative experience forthe consumer. Excessive shrinkage during the fabric finishing processmay result in crease marks on the fabric surface during processing andhousehold washing. Said creases may be very difficult to remove byironing.

There is a need to produce, stretch woven fabrics with high quality, acottony hand, which are breathable, easy to care for, easy to yarnpackage dye and indigo yarn dyes, do not require fabric heat-setting,and are made by a simplified manufacturing process. This includesshirting as well as bistretch denim having a cotton feeling having lowshrinkage, and ease of manufacture.

SUMMARY OF THE INVENTION

The invention comprises methods for making stretch fabric from compositecorespun yarns without heat-setting the fabric in further processing.The invention further comprises stretch fabrics and garments made fromsuch fabrics including shirting and denim.

According to a first embodiment of the method, an elastomeric fiber anda hard fiber are corespun to form a composite corespun elastomeric yarn,wherein the elastomeric fiber is drafted to no more than 2.7× of itsoriginal length during corespin covering. The elastomeric fiber may bebare spandex yarn from 11 to 156 dtex including 11-44 dtex, and the hardfiber may be a hard yarn with a yarn count from about 5 to 80 Ne,including from about 10 to 80 Ne. One suitable hard yarn is cotton.

According to a second embodiment of the method, an elastomeric fiber anda hard fiber are corespun to form a composite corespun elastomeric yarn,using customary drafting of 3.0× or more. After the corespun compositeyarn is formed, it is pre-treated with hot water or steam at atemperature of at least 110° C. before dyeing or weaving. Thepretreatment with steam may be in an autoclave at a temperature of from110° C. to 140° C. including 110° C. to about 130° C. for 6 to 60minutes. The pretreatment with hot water may be in a yarn package dyerat a temperature of from 110° C. to 140° C. including 110° C. to about130° C. for about 5 to 30 minutes. For this alternate embodiment, theelastomeric fiber used to form the composite corespun yarn may be barespandex yarn from 22 to 156 dtex, and the hard fiber may be a hard yarnwith a yarn count from 5 to 80 Ne, including from about 10 to 80 Ne. Onesuitable hard yarn is cotton.

A fabric is woven using the composite corespun elastomeric yarn producedby one of these alternate methods. The composite corespun elastomericyarn is used in at least the weft direction. They also can be used inwarp or both warp and weft directions. Any weave pattern may be used,including: plain, 2/1 twill, 3/1 twill, oxford, poplin, dobby, sateen,and satin. The composite yarn may be used in every warp or weft yarn.They also can be used in alternatively with hard yarn. For example, onecomposite yarn with one hard yarn or one composite yarn with two hardyarns. The composite yarn may be used up to about one composite yarn forevery seven hard yarns. Further processing of the fabric is carried outwithout heat-setting the fabric. Further processing may includecleaning, bleaching, dyeing, drying, compacting, sanforizing, singeing,de-sizing, mercerizing, and any combination of such steps. The compositecore spun yarn can also be used in warp direction in the fabrics.

One exemplary shirt fabric produced by the inventive method has a weightof 175 g/m² or less, and after washing has a shrinkage of 10% or less.Such fabric may have a Fabric Cover Factor between about 45% to about70% in the warp direction and from about 30% to about 50% in the weftdirection. Such fabric may have elongation in the weft direction fromabout 10% to about 45% Such fabric may contain from 1% to 5% by weight,based on the total fabric weight per square meter of spandex as theelastomeric fiber in the composite corespun yarn. The stretch shirtingfabric produced may be formed into a garment.

Another exemplary denim fabric produced by the inventive method of someembodiments has a weight of 238 g/m² or high, and after washing has ashrinkage of 10% or less. Such fabric may have a Fabric Cover Factorbetween about 45% to about 70% in the warp direction and from about 30%to about 50% in the weft direction, elongation in the weft directionfrom about 10% to about 45%, and may contain from 0.3% to 5% by weight,based on the total fabric weight per square meter of spandex as theelastomeric fiber in the composite core spun yarn. The stretch denimfabric produced may be formed into a jean garment.

BRIEF DESCRIPTION OF THE FIGURES

The detailed description will refer to the following drawings, whereinlike numerals refer to like elements and wherein:

FIG. 1 is a schematic description of a core-spinning draft apparatus;

FIG. 2 is a block diagram of a method for forming a woven shirtingfabric according to existing methods;

FIG. 3A is a block diagram of a method for forming a stretch wovenshirting fabric according to a first embodiment of this invention;

FIG. 3B is a block diagram of a method for forming a stretch denimfabric according to a first embodiment of this invention;

FIG. 4 is a block diagram of a method for forming a stretch wovenshirting fabric according to a second embodiment of this invention; and

FIG. 5 is a block diagram of a method for forming a stretch wovenshirting fabric according to a third embodiment of this invention.

DETAILED DESCRIPTION OF THE INVENTION

In one embodiment of the method of this invention, the heat-setting andyarn-twist set steps commonly used in existing fabric forming methods(such as illustrated in FIG. 2) can be eliminated by using spandex yarnswith a lower denier and lower draft to make the core-spun covered yarn.We found that when the total spandex draft, as measured in the compositeyarn, can be between 1.5× and 2.7×, a more open fabric can be createdthat has improved fabric quality, including a cottony hand and good airpermeability. Flat, stable fabrics can be formed without heat-settingincluding fabrics having weights below 175 g/m². In addition, fabricprocessing improvements may include ease of yarn package dyeing, andease of indigo yarn dyeing for denim.

FIG. 3A illustrates this first embodiment of a method for making astretch shirting fabric. Like reference numerals indicate like steps inFIGS. 2 and 3A, however, the reference numerals include also an “a”designation in FIG. 3A to emphasize that the core-spinning is carriedout differently, and thereafter a corespun yarn with differentproperties is processed in this first embodiment. Referring to FIG. 3A,an elastomeric fiber and a hard fiber, denoted as cotton in FIG. 3A, arecombined by a core-spinning process to form a core spun yarn 10 a.

The elastomeric fiber, which may be spandex, is drafted only to 1.5× to2.7× of its original length during the core-spinning process. This is alower range than was used in existing core-spinning for fabrics. Thedraft value range of 1.5× to 2.7× is the total draft of the spandex,which includes any drafting or drawing of the spandex that is includedin the supply package of as-spun yarn. The value of residual draft fromspinning is termed package relaxation, “PR”, and it typically rangesfrom 0.05 to 0.15 for the spandex used in composite yarn for wovenfabrics The total draft of the spandex in the composite yarn istherefore MD*(1+PR), where “MD” is the composite machine draft.Referring to FIG. 1 as illustrative, the composite machine draft iscalculated as the ratio of front roller 42 speed to feed roller 46speed.

Because of its stress-strain properties, spandex yarn drafts more as thetension applied to the spandex increases, conversely, the more that thespandex is drafted, the higher the tension in the yarn. If the totalspandex draft in the composite yarn is higher than 2.7×, the yarns canhave high power which can result in a jammed or tight fabric weavestructure. Conversely, if the total spandex draft in the composite yarnis lower than 1.5×, the woven fabric may be unable to generate enoughstretch to meet requirements for comfort.

In FIG. 3A, the corespun elastomeric composite yarn is then wound up 14a, rewound 18 a, scoured, and/or bleached and dyed 16 a, and rewound 18a in preparation for weaving 20 a. Different from the typical yarntreating steps of the method set out in FIG. 2, the corespun elastomericcomposite yarn in the method of the invention is not twist set.

The treated corespun yarn is then woven to form a fabric 20 a. Thecorespun elastomeric composite yarn preferably is used as the weft inthe weave for a shirting fabric. The corespun elastomeric composite yarnalso can be used in the warp direction, although more frequently anonelastomeric yarn will be used in the warp. Following weaving, thefabric formed has sufficient stretch and a cottony hand without the needfor heat-setting. The fabric maintains shrinkage of less than about 10%even without heatset. Different from the typical fabric treating stepsof the method set out in FIG. 2, the stretch woven shirting fabric inthe method of the invention is not heat set. The fabric otherwise may bepost-processed as is customary in the industry, such as, for exampleshown in FIG. 3, de-sizing 22 a, scouring, and/or bleaching and dyeing24 a, and sanforizing 28 a.

Representative hard yarns include yarns made from natural and syntheticfibers Natural fibers may be cotton, silk, or wool. Synthetic fibers maybe nylon, polyester, or blends of nylon or polyester with naturalfibers.

One exemplary corespun composite yarn for stretch woven shirting fabricsincludes spandex as the elastomeric fiber and cotton as the hard fiberor yarn covering the spandex The spandex may have 17 to 33 dtex, forexample 22 to 33 dtex. For this composite yarn, the spandex draft iskept at about 2.7× or less When the hard fiber or yarn is cotton, thehard yarn count, Ne, may be about 20 to about 80, for example from about30 to about 60.

Commercially useful, elastic, fabrics such as shirting fabricscontaining composite yarns of spandex and cotton can be made withoutheat-setting where the spandex draft is kept at about 2.7× or less. Thecontent of spandex in the representative fabric, on a % weight basis, isfrom about 1.5% to about 5%, for example from about 2% to about 4%. Forthis fabric, the Fabric Cover Factor, which characterizes the opennessof the shirt structure, is between about 45% and about 70%, and istypically 55% in the warp direction and between about 30% and about 50%,and is typically 40% in the weft direction. The fabric has an elongationin the weft direction of about 10% to about 45%, including from about15% to about 45% and from about 20% to about 35%.

The draft of the elastomeric fiber during the core-spinning with thehard fiber may vary depending on the denier of the elastomeric fiber. Asuitable fabric may be prepared with a core-spun yarn where the denierof the elastomeric fiber is about 44 dtex or less and the draft is about3.5× the original length. Other suitable yarns include those there thedenier of the elastomeric fiber is about 33 dtex or less including 22dtex or less and the draft is about 3 2× the original length and wherethe denier of the elastomeric fiber is about 22 dtex or less and thedraft is about 2.7 dtex or less.

By eliminating the high-temperature heat-setting step 26 in the method,the new method may reduce heat damage to certain fibers (i.e., cotton)and thus may improve the hand or feel of the finished fabric. As afurther benefit, heat sensitive hard yarns can be used to make stretchshirting fabrics in the new method, thus increasing the possibilitiesfor different and improved products. In addition, eliminating processsteps previously required shortens manufacturing time and improvesproductivity.

For many end uses, composite yarns containing spandex need to be dyedbefore weaving. Package yarn dyeing is the simplest and most economicalmethod for processing composite yarns. For composite yarns comprised ofcotton and elastomeric fiber(s), yarn package dye processing can beproblematic. Specifically, the elastomeric core yarn will retract at thehot water temperatures used in package dyeing. In addition, thecomposite yarn on the package will compress and become very tight,thereby impeding the flow of dyestuffs into the interior of the yarnpackage. This often can result in yarn with different color shades andstretch levels, depending on the yarn's diametral position within thedyed package. Small packages are sometimes used for dyeing compositeyarns to reduce this problem. However, small-package dyeing isrelatively expensive because of extra packaging and handlingrequirements.

We found that a spandex/cotton corespun composite yarn made with lowerspandex draft of the first embodiment of the invention performs betterin yarn dyeing processes. The yarn does not have the excessiveretractive power on the package that otherwise would create high packagedensities that lead to uneven dyeing. The method of the invention thusenables cone-dyeing of composite elastic corespun yarn without the needfor special cone design and special handling.

These new stretch woven shirting fabrics can have a very good cottonyhand. They have a gentle and natural touch and a better drape.Traditional stretch woven fabrics are usually too stretchy and feel toosynthetic.

We also found that a spandex/cotton core spun yarn made with lowerspandex draft of one embodiment of the invention have better performanceduring indigo yarn dyeing process. The yarn does not have extra powerduring indigo dye process that leads to uneven warp sheet duringweaving.

FIG. 3B shows the processing steps of this invention in the applicationof denim indigo process The composition yarn with low draft can beindigo dyed in the form of yarn rope dye, slasher dye and beam dyeing.

Another benefit of the stretch woven fabric of some embodiments is anincreased air permeability. Due to a lower contractive force of the newelastic composite yarn, the finished stretch woven fabrics keep a moreopen structure than is typically found in traditional stretch wovenshirting fabrics. This feature may allow the fabrics to have higher airpermeability and feel more breathable. Persons wearing garments formedfrom the shirting fabric experience greater comfort because of thehigher air permeability.

In a second embodiment of the invention, the heat-setting and yarn-twistset steps commonly used in existing fabric forming methods (such asillustrated in FIG. 2) can be eliminated by pre-treating the corespuncomposite yarn with high temperature steam prior to weaving.

Stretch composite yarns with spandex often undergo steaming in anautoclave prior to warping or weaving. Typically, the purpose of thisprocess is to reduce the liveliness of the composite yarn. It is usuallycalled steam set, or alternately twist set. After steam setting of theyarn, the tendency towards snarl formation of the yarn will be reduced,which gives better dimensional stability of yarn and ensures betterperformance during weaving operation. Under such processing conditions,spandex can be just temporally “set”. The “frozen” power can come backin following finishing processing.

We found that when the traditional spandex composite yarns were steampretreated in an autoclave under temperatures between about 110° C. toabout 14° C., the yarn potential stretch levels reached from about 20%to about 40% FIG. 4 is a block diagram setting out the method of thesecond embodiment. Like reference numerals indicate like steps in FIGS.2, 3 and 4, however, the reference numerals include also a “b”designation in FIG. 4 to emphasize that the corespun composite yarn issteam set differently, and thereafter a corespun yarn with differentproperties is processed in this second embodiment.

Referring to FIG. 4, an elastomeric fiber is core spun with a hard fiberor hard yarn, denoted as cotton in FIG. 4 to form a corespun yarn 10.Different from the first embodiment of the method set out in FIG. 3,during the core-spinning step, the elastomeric yarn may be drafted atconventional draft levels, such as 3.5× to 3.8×.

The corespun yarn is then pretreated by steam-setting 32. Preferably,two cycles of steam set processing are used, first cyclesteaming→vacuum→second cycle steaming. The steam temperature can bebetween about 110° C. to about 140° C. The steaming time may depend onthe package size. For example, for cops with about 80 to about 100 gramsof composite yarn, first and second cycle steaming time can be about 6to about 8 minutes and about 16 to about 20 minutes, respectively. For 1Kg weight bobbins, it may take 20 minutes and 60 minutes in first andsecond cycles, respectively After such pretreatment steam setting, theyarn potential stretch for the steam treated composite yarn can be verysimilar to yarn made through the low draft method as disclosed in thefirst embodiment.

Following the pretreatment steam setting, the composite yarn isprocessed as customary in the industry. Exemplary steps are set out inFIG. 4. The composite yarn is wound up 14 b, rewound 18 b, scouredand/or bleached, dyed 16 b, rewound 18 b, and woven to form a shirtingfabric. Preferably, the composite yarn forms the weft The fabric is thentreated as desired and customary in the industry, except that the fabricneed not be heat set. As shown in FIG. 4, the fabric may be singed 21 b,de-sized 22 b, scoured and/or bleached and dyed 24 b, and sanforized 28b. The fabric made from such yarns exhibits good hand, low shrinkage,and good air permeability—breathability.

By varying the steaming temperature in the pretreatment steam set (step32 in FIG. 4), the yarn potential stretch levels can be varied. Thisenables a method to tailor the yarn for different fabric styles andpatterns. The advantage of this new approach is low cost. In contrast toexisting systems, this new method may enable 40D and 70D spandex to beused in composite yarns in additional to utilizing higher draft levelsin making said yarns.

After the pretreatment steam setting step, the extra contractive powerof the elastic composite yarn is diminished. In the ensuing textileprocesses, the yarn behaves more like rigid cotton yarn It is easier tofinish by yarn dyeing (step 16 b in FIG. 4) and to weave (step 20 b inFIG. 4). The fabric will have no extra shrinkage in finishing, whichdiminishes crease marks on the fabric surface. In addition, although amanufacturer may choose to heat set the fabric, such heat-setting is notbe required. It also may provide low stretch and low growth stretchwoven fabric with better cotton-like hand. For spinning processes, nospecial care is required.

Preferably, steam set temperature on the composite yarns should bebetween about 110° C. to about 135° C. For normal spandex, the steamsetting temperature is about 116° C. to about 135° C., but for spandexwith higher heat-setting efficiency, such as Lycra® spandex type 563,the steam-setting temperature is about 112° C. to about 116° C.

In a third embodiment of the invention, the heat-setting and yarn-twistset steps commonly used in existing fabric forming methods (such asillustrated in FIG. 2) can be eliminated by pre-treating the corespuncomposite yarn with a hot water set prior to yarn dyeing or weaving.FIG. 5 is a block diagram setting out the method of the thirdembodiment. Like reference numerals indicate like steps in FIGS. 2, 3, 4and 5, however, the reference numerals include also a “c” designation inFIG. 5 to emphasize that the corespun composite yarn is pretreateddifferently, and thereafter a corespun yarn with different properties isprocessed in this third embodiment. Referring to FIG. 5, an elastomericfiber is core spun with a hard fiber or hard yarn, denoted as cotton inFIG. 5 to form a corespun yarn 10. Different from the first embodimentof the method set out in FIG. 3, during the core-spinning step, theelastomeric yarn may be drafted at conventional draft levels, such as3.0× to 4.0× for 30 to 40 denier spandex.

The corespun composite yarn is then pretreated in hot water 42. Treatingcomposite yarns in hot water is a common practice during yarnpreparation and yarn dyeing processes, such as scouring, bleaching anddyeing. However, most of these conventional operations do not exceed100° C. We unexpectedly found that treating elastic composite yarns withhot water at a temperature from about 110° C. to about 140° C. includingfrom about 110° C. to 132° C. for about 5 to about 30 minutes reducesthe yarn contract power to a desired level for weaving to form a stretchfabric. After such hydro-setting pre-treatment step, the yarn potentialstretch is from about 20% to about 40%, which is very similar to yarnmade via the low draft method as disclosed in the first embodiment.

Normal package dye machinery can be used for this hydro-setting process.Pump pressure should be kept low to obtain uniform treatment. Ingeneral, a pressure—of 15 to 25 pounds per square inch is satisfactoryfor most composite yarns containing 40 to 70 denier spandex. The bypassvalve should be adjusted to give differential pressure between insideand outside flow of 5 to 10 pounds per square inch (35 to 69 kPa).Standard two-way flow, as in conventional dyeing, will assure an evendistribution of heat throughout the package. In some cases, it may usepredominantly inside-to-outside flow or outside-to-inside flow

Through changing the water temperature, the yarn potential stretch canbe controlled. This creates a way to tailor the yarn to match differentfabric style and patterns, which has economic advantages. The machineryused for a hot water set is common to those skilled in the art. Forexample, a Burlington 6# Package Dyer from Burlington EngineeringCompany and Gaston County Dyeing Machine Co. of North Carolina can beused.

Preferably, the water set temperature used on the composite yarn shouldbe between about 116° C. to about 135° C. including from about 116° C.to about 127° C. for about 5 to about 30 minutes. For elastic compositeyarns made with conventional spandex of 40D to 70D denier, settingtemperatures preferably are from about 121° C. to about 135° C.including from about 116° C. to about 127° C. For elastic compositeyarns made with Lycra® spandex type 563, setting temperatures preferablyare from about 116° C. to about 130° C. including from about 116° C. toabout 121° C.

After the hydro setting process, the extra contractive power of spandexcomposite yarn can be diminished. The composite yarns usually have theappearance and characteristics of conventional yarns. In the followingtextile processing, the composite yarn behaves more like rigid cottonyarn.

Referring again to FIG. 5, the hydroset composite yarn is processed ascustomary in the industry. Exemplary steps are set out in FIG. 5. Thecomposite yarn is wound up 14 c, rewound 18 c, scoured and/or bleached,dyed 16 c, rewound 18 c, and woven 20 c to form a shirting fabric. Inone example shirting fabric, the composite yarn forms the weft. Thefabric is then treated as desired and customary in the industry, exceptthat the fabric need not be heat set. As shown in FIG. 5, the fabric maybe singed 21 c, de-sized 22 c, scoured, and/or bleached and dyed 24 c,and sanforized 28 c. The fabric made from such yarns exhibits good hand,low shrinkage, and good air permeability—breathability.

It can be easier to use a composite yarn of this embodiment in yarn dyefinishing processes 16 c and weaving 20 c. Stretch is regenerated by wetrelaxation of the yarn, or in the finishing operation after weaving. Thefabric may not have additional shrinkage in finishing, which may reducecrease marks on the fabric surface. Fabric heat-setting is not required.It also can provide low stretch and low growth fabric with better cottonhand.

We found that the openness of the fabric structure can have significanteffects on the quality parameters for stretch woven shirting fabrics. Ifthe fabric structure on the loom is too open, the fabric can have anunstable structure and excessive stretch. If the fabric structure on theloom is too compact, the fabrics may not generate enough stretch. Theopenness of the fabric can be characterized as “Fabric Cover Factor”,which determines the degree of yarn occupation or cover in fabric.“Fabric Cover Factor” quantifies the number of yarns that areside-by-side as a percentage of the maximum number of the yarns that canlie side-by-side. Because of the reduced retractive power of theelastomeric yarn in this invention, a fabric with more open structurewill not be tightly jammed after finishing. The more open structuregives the fabric lower weight, better air permeability, and a morecottony hand.

We found that good results can be obtained when the warp yarn coverfactor on the loom is about 6% to about 10% lower than typical stretchwoven shirting fabrics. For plain weave fabrics, the preferred FabricCover Factor can be from about 45% to about 70%, and can be typicallyabout 55% in warp direction and from about 30% to about 50%, and can betypically about 40% in weft direction.

Analytical Methods:

Yarn Potential Stretch:

Elastic corespun yarns were formed into a skein with 50 cycles with astandard sized skein reel at a tension of about 0.1 grams per denier.The length of one cycle yarn is 1365 mm The skein yarn was boiled off at100° C. water for 10 minutes under free tension. The skeins were driedin air and were conditioned for 16 hours at 20° C.+/−2° C. and 65%relatively humidity, +/−2%.

The skein was folded over four times to form a thickness which is 16times the thickness of the original skein of yarn. The folded skein wasmounted on an Instron tensile testing machine. The skein was extended toa load of 1000 grams force and relaxed for three cycles. During thethird cycle, the length of skein under 0.04 Kg load force is recorded asL₁, the length of skein under 1 Kg force is recorded as L₀. YarnPotential Stretch (YPS) is calculated as follows:Yarn Potential Stretch (YPS) %=(L ₀ −L ₁)/L ₀*100Woven Fabric Elongation (Stretch)

Fabrics are evaluated for % elongation under a specified load (i.e.,force) in the fabric stretch direction(s), which is the direction of thecomposite yarns (i.e., weft, warp, or weft and warp). Three samples ofdimensions 60 cm×6.5 cm are cut from the fabric. The long dimension (60cm) corresponds to the stretch direction. The samples are partiallyunraveled to reduce the sample widths to 5.0 cm. The samples are thenconditioned for at least 16 hours at 20° C.+/−2° C. and 65% relativelyhumidity, +/−2%.

A first benchmark is made across the width of each sample, at 6.5 cmfrom a sample end. A second benchmark is made across the sample width at50.0 cm from the first benchmark. The excess fabric from the secondbenchmark to the other end of the sample is used to form and stitch aloop into which a metal pin can be inserted. A notch is then cut intothe loop so that weights can be attached to the metal pin.

The sample non-loop end is clamped and the fabric sample is hungvertically. A 30 Newton (N) weight (6.75 LB) is attached to the metalpin through the hanging fabric loop, so that the fabric sample isstretched by the weight. The sample is “exercised” by allowing it to bestretched by the weight for three seconds, and then manually relievingthe force by lifting the weight. This cycle is carried out three times.The weight is allowed then to hang freely, thus stretching the fabricsample. The distance in millimeters between the two benchmarks ismeasured while the fabric is under load, and this distance is designatedML. The original distance between benchmarks (i.e., unstretcheddistance) is designated GL. The % fabric elongation for each individualsample is calculated as follows:% Elongation (E %)=((ML−GL)/GL)×100.

The three elongation results are averaged for the final result.

Woven Fabric Growth (Unrecovered Stretch)

After stretching, a fabric with no growth would recover exactly to itsoriginal length before stretching. Typically, however, stretch fabricswill not fully recover and will be slightly longer after extendedstretching This slight increase in length is termed “growth.”

The above fabric elongation test should be completed before the growthtest. Only the stretch direction of the fabric is tested. For two-waystretch fabric both directions are tested. Three samples, each 55.0cm×6.0 cm, are cut from the fabric. These are different samples fromthose used in the elongation test. The 55.0 cm direction shouldcorrespond to the stretch direction. The samples are partially unraveledto reduce the sample widths to 5.0 cm. The samples are conditioned attemperature and humidity as in the above elongation test. Two benchmarksexactly 50 cm apart are drawn across the width of the samples.

The known elongation % (E %) from the elongation test is used tocalculate a length of the samples at 80% of this known elongation. Thisis calculated as:E(length) at 80%=(E %/100)×0.80×L,

where L is the original length between the benchmarks (i.e., 50.0 cm).Both ends of a sample are clamped and the sample is stretched until thelength between benchmarks equals L+E (length) as calculated above. Thisstretch is maintained for 30 minutes, after which time the stretchingforce is released and the sample is allowed to hang freely and relax.After 60 minutes the % growth is measured as:% Growth=(L ₂×100)/L,

where L₂ is the increase in length between the sample benchmarks afterrelaxation and L is the original length between benchmarks. This %growth will be measured for each sample and the results averaged todetermine the growth number.

Woven Fabric Shrinkage

Fabric shrinkage is measured after laundering. The fabric is firstconditioned at temperature and humidity as in the elongation and growthtests. Two samples (60 cm×60 cm) are then cut from the fabric. Thesamples should be taken at least 15 cm away from the selvage. A box offour sides of 40 cm×40 cm is marked on the fabric samples.

The samples are laundered in a washing machine with the samples and aloading fabric. The total washing machine load should be 2 kg ofair-dried material, and not more than half the wash should consist oftest samples. The laundry is gently washed at a water temperature of 40°C. and spun. A detergent amount of 1 g/l to 3 g/l is used, depending onwater hardness. The samples are laid on a flat surface until dry, andthen they are conditioned for 16 hours at 20° C. +/−2° C. and 65%relative humidity +/−2% rh.

Fabric sample shrinkage is then measured in the warp and weft directionsby measuring the distances between markings. The shrinkage afterlaundering, C %, is calculated as:C %=((L ₂ −L ₁)/L ₁)×100,

where L₁ is the original distance between markings (40 cm) and L₂ is thedistance after drying. The results are averaged for the samples andreported for both weft and warp directions. Positive shrinkage numbersreflect expansion, which is possible in some cases because of the hardyarn behavior

Fabric Cover Factor:

Fabric Cover Factor quantifies the actual number of yarns that are sideby side as a percentage of the maximum number of the yarns that can lieside by side. It is calculated as follows:

The maximum ends of yarn are the number of the yarns that can lie downside-by-side in one inch of fabric in a jammed structure with no yarnsoverlapping. Yarn cover factor (YCF) is mainly determined by yarndiameter or count, expressed as:${Fabric}\quad{Cover}\quad{Factor}\quad\%\frac{{Actual}\quad{{Ends}/{inch}}}{{Maximum}\quad{{Ends}/{inch}}} \times 100$Maximum  Ends/inch = CCF * (Yarn  Count, Ne)^(⩓05)

CCF refers to compact cover factor For 100% cotton ring spun yarn, CCFwas determined to be 28. Yarn count (Ne) represents the yarn size. It isequal to the number of 840 yard skeins required to weigh one pound. Asyarn count values increase, the fineness of the yarn increases.

Fabric Weight

Woven fabric samples are die-punched with a 10 cm diameter die. Eachcut-out woven fabric sample is weighed in grams The “fabric weight” isthen calculated as grams/square meters.

EXAMPLES

The following examples demonstrate the present invention and itscapability for use in manufacturing a variety of light weight wovenfabrics. The invention is capable of other and different embodiments,and its several details are capable of modifications in various apparentrespects, without departing from the scope and spirit of the presentinvention. Accordingly, the examples are to be regarded as illustrativein nature and not as restrictive.

For each of the following nine examples, 100% cotton ring spun yarn isused as warp yarn The 100% cotton yarn used in the warp direction wassized before beaming. The sizing was performed in a Suziki single endsizing machine. PVA sizing agent was used. The temperature in the sizingbath was about 42° C. and the air temperature in the dry area was about88° C. Sizing speed was about 300 yards/minute (276 meters per minute).The residence time of the yarn in the dry area was about 5 minutes.

Lycra® spandex/cotton corespun yarns were used as the weft yarn. Table 1lists the materials and process conditions that were used to manufacturethe corespun yarns for each example Lycra® spandex is available fromInvista S à r.L., of Wilmington, Del. and Wichita, Kans. For example, inthe column headed “Spandex 40d” means 40 denier spandex, T162 or T563Brefers to commercially available types of Lycra®; and 3.5× means thedraft of the Lycra® imposed by the core-spinning machine (machinedraft). For example, in the column headed “Hard Yarn”, 40 is the lineardensity of the spun yarn as measured by the English Cotton Count System(or Ne). The rest of the items in Table 1 are clearly labeled.

Stretch woven fabrics were subsequently made, using the corespun yarn ofeach example in Table 1. The corespun yarns were used as weft yarnsTable 2 summarizes the yarns used in the fabrics, the weave pattern, andthe quality characteristics of the fabrics. Some additional comments foreach of the examples are given below. Unless otherwise noted, theshirting fabrics were woven on a Donier air-jet loom. Loom speed was 500picks/minute. The widths of the fabric were about 76 and about 72 inches(about 193 and about 183 cm) in the loom and greige state, respectively.

Each greige fabric in the examples was finished by first passing itunder low tension through hot water three times at 71° C., 82° C., and94° C. to desize.

Then, each woven fabric was pre-scoured with 3.0 weight % Lubit®64(Sybron Inc.) at 49° C. for 10 minutes. Afterwards it was de-sized with6.0 weight % Synthazyme® (Dooley Chemicals. LLC Inc.) and 2.0 weight %Merpol® LFH (E. I. DuPont Co.) for 30 minutes at 71° C., and thenscoured with 3.0 weight % Lubit® 64, 0.5 weight % Merpol® LFH and 0.5weight % trisodium phosphate at 82° C. for 30 minutes. The fabric wasthen bleached with 3.0 weight % Lubit® 64, 15.0 weight % of 35% hydrogenperoxide, and 3.0 weight % sodium silicate at pH 9.5 for 60 minutes at82° C. Fabric bleaching was followed by jet-dyeing with a black or navydirect dye at 93° C. for 30 minutes. No heat-setting was performed onthese shirting fabrics. TABLE 1 Spandex Hard Yarn Yarn Set Yarn DtexLycra ® Sandex Yarn Setting Temperature Yarn Set Potential Example(Denier) Types Draft (Ne) Method (° C.) Time (min) Stretch (%)  1C 44(40) T162C 3.5X 40 No na na 61.1  2 22 (20) T175C 1.5X 40 No na na 21.4 3 22 (20) T563B 1.5X 50 No na na 31.7  4 22 (20) T175C 1.5X 50 No na na21.4  5 22 (20) T175C 1.5X 50 No na na 21.4  6 22 (20) T162C 1.5X 50 Nona na 21.4  7 44 (40) T563B 3.5X 40 Steam 110 20, 30 29.0  8 44 (40)T162C 3.5X 40 Water 121 20 39.7  9C 44 (40) T563B 3.5X 40 Steam 132 20,30  1.7 10C 44 (40) T563B 3.5X 40 No na na 60.1 11C 40 (40) T162C 3.5X40 Steam 99 20, 30 54.1 12C 40 (40) T563B 3.5X 40 Water 99 20 55.2 13 40(40) T563B 3.5X 40 Steam 121 20, 30 10.0 14 40 (40) T162C 3.5X 40 Steam110 20, 30 43.3 15 40 (40) T162C 3.5X 40 Steam 121 20, 30 37.4 16 40(40) T162C 3.5X 40 Water 132 20 22.5

TABLE 2 Fabric Fabric Warp on loom Finshed Fabric Cover Yarn (warpfabric Fabric Shrinkage Air Factor Ne, 100% Weave EPI × Width WeightFabric Fabric Warp % × Perm Warp % × Example Weft Yarn cotton) patternweft PPI) (cm) (g/m²) Stretch % Growth % Weft %) (CFM) Weft %) 1C 40 Ne80/2 plain 96 × 70 120 194 64 4.2 1.3 × 7.3 4.19 54 × 40 cotton/40DLycra 3.5X CSY 2 50 Ne 80/2 plain 96 × 70 164 122 20 8.2 1.6 × 3.6 22.354 × 36 cotton/20D Lycra 1.5X CSY 3 50 Ne 40 Oxford 96 × 70 138 131 298.2 0.6 × 4.0 33.7 54 × 35 cotton 20D Lycra 1.5X CSY 4 50 Ne 40 2/1twill 96 × 70 146 130 22 5.8 1.3 × 4.4 37.1 54 × 35 cotton/20D Lycra1.5X CSY 5 50 Ne 40 3/1 twill 96 × 70 152 140 32 7.6 2.4 × 3.0 49.1 54 ×35 cotton/20D Lycra 1.5X CSY 6 50 Ne 50 plain 115 × 75 165 115 25 6.80.8 × 0.5 59.8 58 × 38 cotton/20D Lycra 1.5X CSY 7 40 Ne 40 plain 96 ×70 157 144 22 8 1.7 × 3.3 11.6 54 × 40 cotton/40D Lycra 3.5X CSY SteamSet 110° C. 8 40 Ne 40 plain 96 × 70 152 148 33 10 1.7 × 3.2 10.6 54 ×40 cotton/40D Lycra 3.5X CSY Water Set 121° C. 9C 40 Ne 40 plain 96 × 70175 122 6 2.2 2.3 × 0.7 48.5 54 × 40 cotton/40D Lycra 3.5X CSY Steam Set132° C.

EXAMPLE 1C Typical Stretch Woven Shirting Fabric

This is a comparison example, not according to the invention. The warpyarn was 80/2 Ne count of ring spun yarn. The weft yarn was 40 Ne cottonwith 40D Lycra® corespun yarn Lycra® draft was 3.5× in the core-spinningThis weft yarn was a typical stretch yarn used in typical stretch wovenshirting fabrics, with 61% YPS. Loom speed was 500 picks per minute at apick level 70 Picks per inch. Table 2 summarizes the test results. Thetest results show that after finishing, this fabric had heavy weight(194 g/m²), excessive stretch (64%), narrow width (120 cm), high weftwash shrinkage (7.3%) and low air permeability (4.19 cfm). All thesedata indicate that this combination of stretch yarns and fabricconstruction caused high fabric weight and shrinkage. Therefore, thisfabric must be heat set to reduce fabric weight, control shrinkage, andincrease air permeability. Also, this fabric had a harsh and lesscottony hand

EXAMPLE 2 Stretch Poplin Shirting

This sample had the same fabric structure as in example 1C. The onlydifference was the use of low power elastomeric yarn as filling yarn:20D Lycra® under 1.5× draft according to the first embodiment of theinvention. The warp yarn was 80/2 Ne ring spun cotton. The weft yarn was50 Ne cotton/20D Lycra® corespun yarn. The weft yarn had 21% YPS. Theloom speed was 500 picks/minute at 70 picks per inch. Table 2 summarizesthe test results. This sample had lower weight (122 g/m²), good stretch(20%), wider width (164 cm), low weft direction wash shrinkage (3.6%),and good air permeability (22.3 cfm). No heat-setting was carried out onthe fabric, yet fabric appearance and hand were improved over Example 10

EXAMPLE 3 Stretch Oxford Shirting

The warp yarn was 40 Ne 100% cotton ring spun yarn. The weft yarn was 50Ne cotton/20D Lycra® T563B corespun yarn (drafted to 1.5× which is alower draft as per the first embodiment of the invention). Thiselastomeric yarn had 31.7% yarn potential stretch and inserted intofabric as weft yarn at 70 picks/inch on the loom. Oxford weaving patternwas applied The finished fabric had a low weight (131 g/m²). Withoutheat-setting, the sample had 29% stretch and 4.0% wash shrinkage in theweft direction. It is an ideal fabric for making stretch woven shirtingfabric.

EXAMPLE 4 Stretch 2/1 Twill Shirting

This fabric used the same warp and weft yarn as Example 3. Also, theweaving and finishing process were the same as Example 3, but its weavepattern was 2/1 twill Table 2 summarizes the test results. This samplehad proper weight (130 g/m²), good stretch (22%), wider width (146 cm),and acceptable weft direction wash shrinkage (44%). No heat-settingprocess was used, and the fabric appearance and hand was excellent.

EXAMPLE 5 Stretch 3/1 Twill Shirting

The warp yarn was 40 Ne ring spun cotton, and the weft yarn was 50 Necotton/20D Lycra® corespun yarn. The Lycra® draft in the corespun yarnwas 1.5×, which is a lower draft as per the first embodiment of theinvention. The loom speed was 500 picks/minute at 70 picks per inch. Thetest results of finished fabric are listed in Table 2. The samplefurther confirms that low power elastomeric yarn can produce highperformance stretch shirting without requiring special care. The fabricsample had basis weight (140 g/m²), available stretch (32%), width (152cm), and wash shrinkage in weft direction (3.0%), which are acceptablefor shirting applications

EXAMPLE 6 Yarn Dyed Stripe Shirting

The weft yarn was 50 Ne cotton corespun with 20D Lycra® spandex held at1.5× draft, which is a lower draft as per the first embodiment of theinvention. The warp yarn was 50 Ne 100% cotton ring spun yarn. Beforeweaving, the stretch weft yarn went through package pre-treatment,including in rewinding, scouring, bleaching and rewinding. Afterpre-treatment, the package still had good shape. Before weaving, thewarp yarn was also dyed and color strips were formed in the fabric warpdirection. After weaving, the greige fabric was finished in continuousfinishing range. The finish routine was. Preparation range→FinishingRange→Sanforize. In the preparation range, the fabrics passed throughsingeing, desizing, scouring, mercerizing and drying process. Infinishing range, the wrinkle resistant resin and softener were paddedbefore resin curing the fabrics. In the finished fabric, the warp andweft density of the cotton yarn was 147 end/in×80 picks/in, the basisweight was 115 g/m², and the weft elongation was 25%. The fabric hadvery low shrinkage. 0.8% in warp and 0.5% in weft

EXAMPLE 7 Stretch Poplin with Twist Setting Yarn

In this example the fabric had the same warp yarn and same fabricstructure as in Example 2, except 40 Ne cotton/40D Lycra® corespun wasused as weft yarn and the warp yarn was 40 Ne 100% ring spun cotton. TheLycra® was drafted 3.5× during covering process. This yarn was a typicalelastomeric corespun yarn. In this example, the yarn was pre-treated inan autoclave with steam as per the second embodiment of the invention(like FIG. 4) before weaving. Two cycles of steam setting were used:first cycle steaming→vacuum→second cycle. The steam temperature wasabout 110° C. The steaming time for both first and second cycles was 20and 30 minutes, respectively with a 20 minutes vacuum in between FromTable 1, we can see the yarn potential stretch is 29%. During this steamset, the excess power in the yarn was diminished. This yarn potentialstretch (YPS) is very similar to yarn through low draft method asdisclosed in Examples 2 through 6. Table 2 lists the fabric properties.The fabric made from such yarn exhibited good cotton hand, low weftshrinkage (3.3%), good stretch (22%) and wider width (157 cm). No fabricheat-setting was necessary.

EXAMPLE 8 Hot Water Pretreated Yarn

This example had the same warp yarn and same fabric structure as Example7, except the pretreatment step was different. 40 Ne cotton/40D Lycra®corespun yarn was used as the weft yarn. The Lycra® was drafted 3.5×during the core-spin covering process. Before weaving, the weft yarnwent through hot water treatment at about 121° C. for 20 minutes in ayarn dye machine like the method set out in FIG. 5. After hot treatmentand dry, the yarn was inserted into fabric as filling yarn.

From Table 1, we can see the yarn potential stretch was 39.7% Duringthis hot water heat treatment, the excess power in the yarn wasdiminished. The yarn potential stretch in this example was also similarto yarn made through low draft method as disclosed in Examples 2 through6, and similar to the yarn made via the steam setting pretreatmentprocess as disclosed in Example 7.

Table 2 lists the fabric properties. The fabric made from such yarnexhibited good cotton hand, low shrinkage (3.2%), good stretch (33%) andwider width (152 cm). No fabric heat-setting was necessary.

EXAMPLE 9C Shirting Fabric with Minimal Stretch

This is a comparison example, not according to the invention. Thissample had the same fabric structure as in example 8. The onlydifference was the use of elastomeric yarn as filling yarn. The weftyarn was pretreated in hot steam under 132° C. After such treatment, theweft yarn only had 1.7% YPS. The loom speed was 500 picks/minute at 70picks per inch. Table 2 summarizes the test results. This sample hadvery low fabric stretch (6%), which cannot satisfy the comfortrequirement desired for stretch shirting fabrics.

EXAMPLE 10C High Yarn Potential Stretch Yarn

This is a comparison example, not according to the invention. In thisexample, 44 dtex T563B Lycra® spandex yarn was corespun at a draft of3.5× with 40 Ne 100% cotton yarn. No further treatment was done. Thisyarn had a YPS of 60 1%, which was unacceptably high.

EXAMPLE 11C Steam Pretreated Yarn at Low Temperature

This is a comparison example, not according to the invention. In thisexample, 44 dtex T 162C Lycra® spandex yarn was corespun at a draft of3.5× with 40 Ne 100% cotton yarn This yarn was treated with steam at 99°C. for two cycles of 20 and 30 minutes, respectively, with 20 minutevacuum cycles in between the steam cycles. This yarn had a YPS of 54.1%,which was unacceptably high. This comparison example demonstrates thathigher steam temperature is needed to change the YPS of the yarn

EXAMPLE 12C Water Pretreated Yarn at Low Temperature

This is a comparison example, not according to the invention. In thisexample, 44 dtex T563B Lycra® spandex yarn was corespun at a draft of3.5× with 40 Ne 100% cotton yarn. This yarn was treated with water at99° C. for 20 minutes. This yarn had a YPS of 55.2%, which wasunacceptably high. This demonstrates that higher water temperature isneeded to change the YPS of the yarn.

EXAMPLE 13 Steam Pretreated Yarn

In this example, 44 dtex T563B Lycra® spandex yarn was corespun at adraft of 3.5× with 40 Ne 100% cotton yarn. This yarn was treated withsteam at 121° C. for two cycles of 20 and 30 minutes, respectively, with20 minute vacuum cycles in between the steam cycles. This yarn had a YPSof 10.0%.

EXAMPLE 14 Steam Pretreated Yarn

In this example, 44 dtex T162C Lycra® spandex yarn was corespun at adraft of 3.5× with 40 Ne 100% cotton yarn. This yarn was treated withsteam at 110° C. for two cycles of 20 and 30 minutes, respectively, with20 minute vacuum cycles in between the steam cycles This yarn had a YPSof 43.3%.

EXAMPLE 15 Steam Pretreated Yarn

In this example, 44 dtex T 162C Lycra® spandex yarn was corespun at adraft of 3.5× with 40 Ne 100% cotton yarn. This yarn was treated withsteam at 121° C. for two cycles of 20 and 30 minutes, respectively, with20 minute vacuum cycles in between the steam cycles This yarn had a YPSof 37.4%

EXAMPLE 16 Water Pretreated Yarn

In this example, 44 dtex T563B Lycra® spandex yarn was corespun at adraft of 3.5× with 40 Ne 100% cotton yarn This yarn was treated withwater at 132° C. for 20 minutes. This yarn had a YPS of 22.5%

1. A method for making a stretch fabric, comprising: (a) core-spinningan elastomeric fiber and a hard fiber to form a composite core-spunelastomeric yarn, wherein the elastomeric fiber is drafted to no morethan about 3.5× of its original length during core-spin covering; and(b) weaving a fabric with the composite core-spun yarn in at least oneof the weft and the warp; and (c) further processing the fabric.
 2. Themethod of claim 1, wherein step (c) in conducted without heat-setting.3. The method of claim 1, wherein the elastomeric fiber is drafted to nomore than about 3.2× of its original length during core-spin covering.4. The method of claim 1, wherein the elastomeric fiber is drafted to nomore than about 2.7× of its original length during core-spin covering.5. The method of claim 1, wherein the elastomeric fiber is bare spandexyarn from about 11 to about 156 dtex.
 6. The method of claim 1, whereinthe elastomeric fiber is bare spandex yarn from about 11 to about 44dtex.
 7. The method of claim 1, wherein the hard fiber is a hard yarnwith a yarn count from about 10 to about 80 Ne.
 8. The method of claim1, wherein the hard fiber is a hard yarn with a yarn count from about 10to about 80 Ne
 9. The method of claim 3, wherein the hard yarn iscotton.
 10. The method of claim 1, wherein the elastomeric fiber is abare spandex yarn from 17 to 78 dtex, the hard fiber is a hard yarn withyarn count from 7 to 60 Ne, and the spandex yarn is drafted no more than2.5× its original length during core-spin covering.
 11. The method ofclaim 5, wherein the elastomeric fiber is bare spandex from about 17 toabout 33 dtex and the hard fiber is a hard yarn with yarn count fromabout 30 to about 60 Ne.
 12. The method of claim 1, wherein oneelastomeric composition yarn can be used for every 7 hard yarns or fewerin the warp or weft direction.
 13. The method of claim 1, whereinfurther processing comprises one or more steps selected from the groupconsisting of: cleaning, bleaching, dyeing, drying, compacting,sanforizing, singeing, de-sizing, mercerizing, and any combination ofsuch steps.
 14. A stretch fabric made by the method of claim 1
 15. Thefabric of claim 14, wherein the Fabric Cover Factor is between about 45%to about 70% in warp direction and from about 30% to about 50% in weftdirection
 16. The fabric of claim 14, wherein the elongation in the weftor warp direction is from about 10% to about 45%.
 17. The fabric ofclaim 14, having a weave pattern selected from the group consisting of:plain, 2/1 twill, 3/1 twill, oxford, poplin, dobby, sateen, and satin.18. The fabric of claim 14, wherein the elastomeric fiber is spandex,and the fabric contains from 1% to 5% by weight, based on the totalfabric weight per square meter of spandex.
 19. A garment formed from thestretch fabric of claim
 14. 20. A method for making a stretch shirtingfabric, comprising: (a) core-spinning an elastomeric fiber and a hardfiber to form a composite core-spun elastomeric yarn; (b) pretreatingthe composite corespun elastomeric yarn with hot water or steam at atemperature of at least 110° C. before dyeing or weaving; (c) weaving ashirting fabric with the composite core-spun yarn in the weft direction;and (d) further processing the fabric without heat-setting.
 21. Themethod of claim 20, wherein the pretreatment is with steam in anautoclave at a temperature of from 110° C. to 140° C. for 6 to 60minutes.
 22. The method of claim 20, wherein the pretreatment is withhot water in a yarn package dyer at a temperature of from 110° C. to140° C. for 5 to 30 minutes.
 23. The method of claim 20, wherein theelastomeric fiber is bare spandex yarn from 22 to 156 dtex and the hardfiber is a hard yarn with yarn count from 5 to 80 Ne.
 24. The method ofclaim 20, wherein the elastomeric fiber is bare spandex yarn from 44 to78 dtex and the hard fiber is a hard yarn with yarn count from 7 to 60Ne.
 25. The method of claim 24, wherein the hard yarn is cotton.
 26. Themethod of claim 20, wherein one elastomeric composition yarn can be usedfor every 7 hard yarns or fewer in the warp or weft direction.
 27. Themethod of claim 20, wherein further processing comprises one or moresteps selected from the group consisting of: cleaning, bleaching,dyeing, drying, compacting, sanforizing, singeing, de-sizing,mercerizing, and any combination of such steps.
 28. A stretch fabricmade by the method of claim
 20. 29. The fabric of claim 28, wherein theFabric Cover Factor is between about 45% and about 70%.
 30. The fabricof claim 28, wherein the elongation in the weft or warp direction isfrom about 10% to about 45%.
 31. The fabric of claim 28, having a weavepattern selected from the group consisting of: plain, 2/1 twill, 3/1twill, oxford, poplin, dobby, sateen, and satin.
 32. The fabric of claim28, wherein the elastomeric fiber is spandex, and the fabric containsfrom 0.2% to 5% by weight, based on the total fabric weight per squaremeter of spandex.
 33. A garment formed from the stretch fabric of claim28.
 34. An article comprising a fabric comprising a core-spuncombination yarn including an elastomeric fiber and a hard fiber,wherein the elastomeric fiber is drafted to no more than about 3.5× ofits original length during core-spin covering and said fabric is woven.35. The article of claim 34, wherein said elastomeric fiber has a denierof about 44 dtex or less.
 36. The article of claim 34, wherein saidelastomeric fiber has a denier of about 33 dtex or less and saidelastomeric fiber is drafted to no more than about 3.2× of its originallength during core-spin covering.
 37. The article of claim 36, whereinsaid elastomeric fiber has a denier of about 22 dtex or less.
 38. Thearticle of claim 34, wherein said elastomeric fiber has a denier ofabout 22 dtex or less and said elastomeric fiber is drafted to no morethan about 2.7× of its original length during core-spin covering. 39.The article of claim 34, wherein said fabric is heat set at atemperature of less than about 180° C. for about 45 seconds or fewer.40. The article of claim 34, wherein said fabric is not heat set. 41.The article of claim 34, wherein the fabric has elongation in the warpor weft direction from about 10% to about 45%,